The present disclosure broadly relates to placing 2D barcodes on documents via metameric colorant combinations. The barcodes can be subsequently distinguished from a background via appropriate IR lighting, utilizing techniques similar to decoding dot peened 2D barcodes. It is to be appreciated, however, that the exemplary embodiments are also amendable to other like applications.
Barcodes are an essential part of communication, tracking and verification of data in today's commerce. Information such as a model number, a manufacturer ID, a part number, a date, a time, etc. can be encoded via a predefined configuration of elements that comprise the barcode. For 1-dimensional (1D) barcodes, data is encoded via widths (lines) and spacings of parallel lines. For 2-dimensional (2D) barcodes, data is encoded via a placement of geometric barcode elements (squares, dots, hexagons, etc.) within a predefined space. Placement can be accomplished via a number of means such as transfer of ink onto a paper substrate, dot-peening of a metal substrate, etc.
2D barcodes are used in a plurality of industries including manufacturing, postal, transportation, government, healthcare, retail and automotive. There are several standards that have been developed for each industry to provide appropriate data encoding including PDF417, QR Code, Aztec Code, Data Matrix, and MaxiCode, for example. An inherent requirement to decode any 2D barcode standard is a suitable contrast level between elements and non-elements to insure accurate recognition of encoded information. Another requirement of conventional 2D barcodes is space to allow placement of the barcode on a substrate. Such placement can create a visual distraction and/or displacement of other information that is of equal or greater importance than the data encoded within the 2D barcode.
Consequently, a strong desire exists to facilitate placement of the barcodes without hindering placement of other information. In one example, particular inks (e.g., clear/invisible infrared ink, UV fluorescent ink, etc.) allow integration of the inks as part of a document design without making the barcode visible or distracting. The use of such conventional invisible inks, however, can result in additional cost or poor contrast between elements that degrades the ability to properly decode these marks. In some cases, the contrast can be a factor of six times lower than standard visible inks, rendering conventional invisible inks unsuitable for consistent accurate data recovery.
Thus, systems and methods are needed to facilitate accurate and consistent encoding and decoding of 2D barcodes that meet particular aesthetic requirements.